1. Field of the Invention
The present invention relates to a liquid electrophotographic printer, and more particularly, to an apparatus for recovering a liquid carrier contained in a developer liquid supplied to a photoreceptor belt.
2. Description of the Related Art
An electrophotographic printer such as a laser color printer supplies a developer liquid in which a toner is mixed with a liquid carrier such as NORPAR, commercially available from Exxon, to an electrostatic latent image formed on a photoreceptor belt, and develops the electrostatic latent image. The carrier is then recovered by a carrier recovery apparatus.
FIG. 1 shows a carrier recovery apparatus employed in a conventional liquid electrophotographic printer. Referring to FIG. 1, in a manifold 21, there are provided a drying roller 22 for absorbing the liquid carrier from a photoreceptor belt 14 while rotating in contact with the photoreceptor belt 14, and a heating roller 23 for heating the drying roller in contact therewith and evaporating the absorbed carrier.
The evaporated gas carrier is accommodated within the manifold 21. Since a multitude of heat exchanging fins (not shown) are formed on the outer surface of the manifold 21, the gas carrier is condensed on the inner surface of the manifold 21 by heat exchange. The condensed liquid carrier is collected from the inner surface of the manifold 21 to then be induced to a cartridge 26 through a first recovery tube 25.
Further, the uncondensed gas carrier of the manifold 21 is induced to a condenser 28 along a supply line 27 by the driving of a supply fan 29. Since a liquid condensed carrier 28a is contained in the condenser 28, the induced gas carrier is liquefied by the heat exchange with the condensed carrier 28a. Then, the condensed liquid carrier is recovered in the cartridge 26 through a second recovery tube 31.
Also, the gas carrier which is not condensed in the condenser 28 is filtered via a filter 34 made of active carbon, together with the air exhausted by an exhaust fan 33 to the outside.
Reference numeral 30 represents a peltier chip for keeping the internal temperature of the condenser 28 constant, and reference numeral 32 represents a moisture reservoir, for separating moisture from the liquid carrier 28a stored in the condenser 28 and storing the same.
Since NORPAR, which is typically used as the carrier is an environmentally hazardous material, it is necessary to prevent the carrier from being effused.
Therefore, in order to increase the filtering capacity of the filter 34, the thickness (T) of the filter 34 must be large. In this case, the exhausting capacity of the exhaust fan 33 is noticeably reduced. To solve this problem, a large exhaust fan and a driver therefor (not shown) are employed. However, the overall structure of the printer becomes bulky.